Merge pull request #14581 from Microsoft/foreachchild

Expose `forEachChild` as a method of Node

Author: Andy

src/services/services.ts

@@ -210,6 +210,10 @@ namespace ts {
 
             return child.kind < SyntaxKind.FirstNode ? child : child.getLastToken(sourceFile);
         }
+
+        public forEachChild<T>(cbNode: (node: Node) => T, cbNodeArray?: (nodes: Node[]) => T): T {
+            return forEachChild(this, cbNode, cbNodeArray);
+        }
     }
 
     class TokenOrIdentifierObject implements Node {
@@ -283,6 +287,10 @@ namespace ts {
         public getLastToken(): Node {
             return undefined;
         }
+
+        public forEachChild<T>(): T {
+            return undefined;
+        }
     }
 
     class SymbolObject implements Symbol {

src/services/types.ts

@@ -18,6 +18,8 @@ namespace ts {
         getText(sourceFile?: SourceFile): string;
         getFirstToken(sourceFile?: SourceFile): Node;
         getLastToken(sourceFile?: SourceFile): Node;
+        // See ts.forEachChild for documentation.
+        forEachChild<T>(cbNode: (node: Node) => T, cbNodeArray?: (nodes: Node[]) => T): T;
     }
 
     export interface Symbol {